CT-water first test.
Performed with:
Flux 20 LMH (permeate flow 17 mL/min)
Crossflow of 0.5 m/s (feed flow 1160 mL/min)
Initial feed volume of approx. 4L.
Time duration 24 h.
The following plots show the pressure before and after the membrane as well as TMP. The initial pressure is 3.2 bar which decease to about 2.5 bar, which is the pressure observed at previous experiments. There is large pressure fluctuations every 2 hours, this might be due to the experimental set up, where 2L of permeate is dumped into the feed tank, which only contain about 4L initially. This might cause air bobbles to enter the system, this air enter the pressure dampener and cause fluctuations in the pressure, it is also observed that these fluctuations become more severe as the experiment go on. The pressure seems to stabilize at around 2.5 bar after the 2 initial hours, it was expected that the pressure would increase rather than decrease due to fouling.
The conductivity of feed and permeate stream is plotted with the following plot, as well as calculated rejection. Due to the experimental set up with re circulation of permeate introduced every 2 hours this cause large fluctuation in conductivity. The feed conductivity is initially 1000 S/cm and increase to about 1300 S/cm within 2 hours, were it afterwards decrease to 1000 S/cm again. This give similar fluctuation in permeate where the conductivity increase from 400 S/cm to about 500 S/cm every 2 hours. <- hvilket vi ikke forstår, den burde falde . This also cause fluctuation in the rejection but over all the rejection decrease and becomes steady around 55-60%.
## Warning in RColorBrewer::brewer.pal(N, "Set2"): minimal value for n is 3, returning requested palette with 3 different levels
## Warning in RColorBrewer::brewer.pal(N, "Set2"): minimal value for n is 3, returning requested palette with 3 different levels
The pH was initially 8.8 (measured on external pH meter to 8.85) and increase slightly to in every 2 hour cycle, but overall the pH decrease from pH 8.8-8.7.